The present invention generally relates to reinforcing carriers or core metal inserts for weatherseals and, more particularly to weatherseals used on components of motor vehicles such as luggage trunks, engine compartments, doors, and windows.
Weatherseals or weatherstrips typically have a longitudinally extending channel-shaped portion for gripping flange joints such as those which extend around openings in motor vehicles. The weatherseals typically include a channel-shaped reinforcing carrier or core metal insert which is embedded within a flexible covering material such as plastic, rubber, polyurethane, or other elastomer. The carrier should be sufficiently strong to perform its desired gripping function yet sufficiently flexible to allow the weatherseal to be curved or bent to fit the contours of the flanges upon which the weatherseal is mounted.
There are many different types of core metal inserts. For example, U.S. Pat. Nos. 5,783,312, 5,871,682 and 6,079,160, each disclose a core metal insert that is continuous, i.e. is a continuous strip of metal, along the entire length of the weatherseal that it reinforces. This type of core metal insert provides adequate structural stability and rigidity to the weatherseal so that it does not lose its shape during installation or subsequent use. However, these continuous core metal inserts significantly limit the flexibility of the weatherseal in which they are embedded, often making it difficult to form the weatherseal to the highly curvilinear paths of door- and window-frames in ever-increasingly aerodynamic and modernistic automobile designs.
U.S. Pat. No. 4,695,499 discloses a core metal insert for a weatherseal that is designed to break apart into a multiplicity of largely independent core members inside the weatherseal to increase the flexibility of the strip. In this design, the core metal insert is provided with a plurality of slits leaving thin webs of metal disposed along the length of the core. According to the reference, these thin webs of metal are broken when the strip is run over a roller of suitable radius, thereby providing the multiplicity independent core members described above. However, in practice it has been found that this arrangement does not reliably result in breaking apart of all or substantially all of the individual core members. Often in practice, there may be groups of 2, 3, 4, 5, or more core members that were not separated by the above-described process.
In addition, to the above, another problem exists in prior-art core metal inserts. In order to ensure that a core metal insert will break apart into its individual members, the core metal insert is initially manufactured having as little material connecting adjacent members as possible. In one such design, the insert is manufactured as a flat metal ribbon with a continuous longitudinally-extending central strip, having laterally-extending tines attached to either side of the central strip. The tines must be bent 90° in order to provide the core metal insert in the conventional U-channel shape so that the weatherseal can be fixed to the associated door- or window-frame, or other installation. Experience has shown that a large number of the laterally-extending tines are broken off of the central strip during the bending process. The resulting weatherseal lacks structural rigidity where the tines are broken, thus largely defeating the purpose for providing the insert within the weatherseal at all.
Accordingly, there is a need in the art for an improved core metal insert for reinforcing a weatherseal which provides sufficient flexibility so that the weatherseal is easily bent without undesirable deformation of the weatherseal. Preferably, such an improved core metal insert will reliably provide separable core metal insert members wherein substantially all of the members will be separated from one another, and also wherein the laterally-extending tines do not break off upon bending to a U-channel shape.